user_has_weapon(player, CSW_USP, 0)
// тоже самое
set_pev(player, pev_weapons, pev(player, pev_weapons) & ~(1 << CSW_USP))
user_has_weapon(player, CSW_USP, 1)
// тоже самое
set_pev(player, pev_weapons, pev(player, pev_weapons) | (1 << CSW_USP))